Rapid advancements in medicine are increasingly providing physicians with opportunities to treat medical conditions at an earlier stage leading to an increase in positive outcomes for their patients. Advancements in the fields of pharmaceutical substances, biotechnology, medical procedures as well as medical devices often drive these advancements. However, such advancements are also leading to an increase in the need of a physician to obtain a portion of tissue from the body to properly diagnose or confirm the medical condition.
In those cases where the physician suspects cancer, the physician attempts to confirm the diagnosis using any number of procedures including non-invasive imaging or even physical palpation to inspect the suspected site. Next, the physician typically obtains a sample of tissue (via a biopsy procedure) to confirm the presence or absence of the disease. A physician can perform a biopsy procedure either using open surgical techniques or minimally invasive/percutaneous techniques. While an open biopsy allows the greatest amount of access to the site, there are also a considerable number of adverse consequences with open procedures. Aside from the cost and recuperation time for the patient, the procedure often must be performed on an already sick patient, who may incur additional side effects. In contrast, a minimally invasive or percutaneous procedure removes a core sample of the suspected tissue mass or lesion. Such procedures are performed with needle or coring type devices. The sample can be aspirated or ejected from the needle for proper evaluation.
Such minimally invasive biopsies can include fine needle aspiration (FNA), transbronchial needle aspiration (TBNA), or core biopsies. In a FNA biopsy, the physician obtains a group of cells for cytological examination.
However, such examination often only allows an examination on the cellular level and often only after the results are processed through a medical laboratory. In a core biopsy, the physician obtains a core sample of tissue for histological examination which may be done after the core tissue sample is frozen or put in a preserving substance (e.g., formalin, a paraffin material or other material that preserves the structure of the tissue). Although any number of biopsy procedures may be required depending on the suspected condition or disease, a core biopsy can be extremely useful and are frequently desired and if available chosen by physicians.
A basic biopsy technique requires considerable manual dexterity and coordination. Such procedures often require the use of both hands, to advance a stylet while maintaining the position of a cannula and then to maintain the position of the stylet while advancing the cannula. Problems can occur if the physician advances the cannula too slow. Slow advancement often results in a poor cutting action and allows the surrounding tissue an opportunity to collapse, or displace without efficient cutting of the cored tissue. Additional complications can occur if the tissue to be sampled contains areas of higher density than that of surrounding tissue. Such discrepancies can occur with calcification commonly associated with certain types of cancerous growths. Slow device advancement may result in the device deflecting against dense tissue. This causes the trajectory of the cannula/stylet structure to move around the dense area and into the more compliant surrounding tissue, potentially missing the intended target.
Many core samples are obtained using a biopsy gun. The term “biopsy gun” often refers to a tissue sampling or coring device designed for single-handed manipulation by a physician. Often, the shape of the “biopsy gun” is adapted to fit within a hand of a medical practitioner via a pistol-like or syringe-like grip, complete with a triggering mechanism that relies upon a spring mechanism to drive the cannula to sever the tissue core. However, such devices are of a relatively complex design resulting in a relatively inflexible device and are typically intended for accessing areas such that are not remotely located within the body (such as the skin surface, breast tissue, etc.).
There is also a compelling need and desire to minimize the burden on the patient by obtaining such a core sample of tissue from deep within the body through minimally invasive means. Doing so can significantly decrease the cost of the procedure as well as the recuperation time of the patient. Moreover, devices and methods that allow less invasive means of obtaining tissue samples from deep within the body can also decrease any reluctance to obtain the sample of tissue, thereby increasing the frequency of occurrence for deep core biopsy procedures.
Many times cancerous tumors, pre-malignant conditions and other diseases or disorders occur within organs or at sites remotely within the body. In such cases, obtaining a tissue sample from the suspected diseased site presents a number of challenges. First, a sample must be obtained without causing inadvertent damage to the patient. Secondly, the physician must obtain a sufficient size of a tissue sample in order to determine the nature or state of the disease. Third, the target tissue might be located within tortuous anatomy of the body and adjacent to other tissue structures or organs. Clearly, any number of additional concerns exists when trying to obtain a desirable tissue sample.
A number of challenges arise when performing procedures through an endoscope, bronchoscope, or other such device. For example, there is a risk that the biopsy device might disrupt structures beneath a tissue surface (such as blood vessels), where the disruption then causes significant complications or effects that may prolong the procedure.
One such area is within the airways of the lungs where puncturing of a blood vessel beneath the airway surface can result in significant bleeding. In cases where a scope type device is used, the bleeding obstructs the ability of the medical practitioner to visualize the damaged area resulting in an escalation of complications. In some cases, a patient's chest must be opened to stem the bleeding.
Scanning for blood vessels underneath the airway wall mitigates the above described problem but is not without its own challenges. For example, because airway or other lung tissue moves due to tidal motion of the lungs (as a result of the mechanics of breathing), it is difficult to visually identify the area that was scanned for blood vessels unless the scanning device remains relatively stationary against the tissue. Moreover, the difficulty increases when considering that the procedure takes place through the camera of a bronchoscope or endoscope.
Aside from the risk to the patient, once the medical practitioner punctures a blood vessel, that practitioner is understandably hesitant or risk adverse when performing future procedures. As a result, while the benefit of these procedures is well known, the risks of complications may reduce the overall success of the procedure.
The devices, systems, and methods described herein allow for obtaining a core sample of tissue much like that obtained with a biopsy gun, but allow for obtaining the sample of tissue using a minimally invasive approach to access remote areas of the body. For example, such areas include but are not limited to the lungs, the liver, the digestive tract, organs within the thoracic cavity, etc. Furthermore, the devices, systems, and methods allow for improved safety when obtaining such biopsy samples.